A Commons inquiry into Britain’s relationship with Saudi Arabia and Bahrain has been condemned for taking secret evidence from BAE Systems.

Human rights groups said that the refusal to publish minutes of the meeting with the defence giant risked jeopardising the transparency and impartiality of the investigation by the Foreign Affairs Select Committee.

They said that the choice as an adviser of Sir William Patey, an Arabist who was ambassador to Riyadh from 2007 to 2010, raised fears of a whitewash when the inquiry concludes in the autumn.

The pressure group Campaign Against the Arms Trade wrote to Richard Ottaway,